It took two years for Pierre Zufferey to capture this spectacular footage of debris flow in Illgraben, Switzerland.
Unlike landslides or mudflows, debris flows are composed of rocks, boulders, and trees. Debris flows are typically the result of sudden rainfall, or a rapid snowmelt.
The Illgraben is an active alpine catchment, which generates a large number of debris flows, including this one occurred on July 22, 2016, according to the Youtube page.
The video captures many characteristics of a debris flow with huge boulders tumbling chaotically.
Watch and be amazed by this natural spectacle!